#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=5e5+100;
typedef  long long LL;
const LL mod=998244353;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
LL num[maxn];
LL ksm(LL a,LL k){
    LL res=1;
    while(k>0){
        if(k&1) res=res*a%mod;
        k>>=1;
        a=a*a%mod;
    }
    return res%mod;
}
int main(void)
{
  cin.tie(0);std::ios::sync_with_stdio(false);
  LL n,m;cin>>n>>m;
  if(m==1){
    cout<<"0"<<"\n";return 0;
  }
  for(LL i=1;i<=n;i++) num[i]=( (n-i)%mod*ksm(i+1,m-2)%mod )%mod;
 // for(LL i=1;i<=n;i++) cout<<num[i]<<" ";
  ///cout<<"\n";
  LL ans=0;
  for(LL i=1;i<=n;i++) ans=(ans%mod+(num[i]%mod*i%mod)%mod)%mod;
  cout<<ans<<"\n";
return 0;
}
